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We randomly select 100,000 samples of size n from a population.  We calculate the sample mean (X-bar) for each of the 100,000 random samples and graph the relative frequency distribution for these 100,000 values of X-bar.  This relative frequency distribution is called the ____________________ of X-bar.

The variable measured in an experiment (e.g., weights of dogs, litter sizes of rabbits, etc.) is called the ____________.

The weights (in pounds) of 17 pigs are used to construct the following stem-and-leaf display (the first two digits were used as the stem and the last digit was used as the leaf): Stem                   Leaf                                       16          0     5 17          — 18          — 19          — 20          — 21          — 22          2     4     6 23          0     9 24          0     1     2     3     4     5     9 25          3 26          — 27          — 28          0     5   Based on this stem-and-leaf display, the median weight is __________ lb.

The body weight in pounds (variable X) and fleece weight in pounds (variable Y) of a random sample of four ewes are as follows: Body weight, lb (X)            Fleece weight, lb (Y)           140                                            9           145                                          10           155                                          10           160                                          12                                                                                      Derive the equation for the regression line.  What would be the predicted fleece weight of a ewe that weighs 152 lb?

A farmer weighs his calves on the day they are weaned.  The weight of the lightest calf is 300 lb and the weight of the heaviest calf is 650 lb.  Based on this information, which measure of variation could be calculated?

Suppose a 99% confidence interval for the population mean for weight of cows of a certain breed turns out to be (800 lb, 1400 lb).  To make more useful inferences from the data, it is desired to reduce the width of the confidence interval.  Which of the following will result in a reduced width of the confidence interval?

Assume that the mean length of time required to complete the Columbus Marathon was 4.5 hours and that the standard deviation of the times was 0.50 hours.  Assume that the racing times were approximately normally distributed.  Only 10% of the runners would be expected to complete the race in less than x hours.  Find the value of x.

The Central Limit Theorem is important in statistics, because:

We construct the following 95% confidence interval for the mean weaning weight of a population of Angus calves:  (500 lb, 600 lb) Which one of the following statements is the correct interpretation of this 95% confidence interval?

In order to compare the means of two populations, independent random samples are selected from each population, with the following results:                                             Sample 1     Sample 2 Sample size                            500                400 Sample mean                       5,280             5,240 Sample standard deviation     150                200 Construct a 95% confidence interval for the difference in the two population means.